BREAKDOWN ON HOW TO VERIFY NYSC CERTIFICATE FOR ALL CORPS MEMBERS.
(1) Write a letter of request to the
Director-General,
National Youth Service Corps, Directorate Headquarters,
Plot 416, Tigris Crescent, Maitama, Abuja.

It should be marked "Attention: Director (Corps Certification)"

(2) Make photocopies of the Certificate(s) you want to verify, serially numbered with your marker or pen and attach them to the letter.
Please note that these are the Certificates produced by the National Youth Service Corps:
1. Certificate of National Service
2. Certificate of Exemption
3. Letter of Exclusion

(3) Submit your letter to the Director-General’s Registry on the sixth (6th) floor of the complex, that is, Yakubu Gowon House – NYSC NDHQ and await your reply.

(4) Other information to note:
1. Ensure to reflect your e-mail address
2. Ensure to reflect your telephone number and
3. Ensure to reflect your traceable contact address on your letter to us.

SOURCE: http://www.belmadeng.com/2016/12/how-to-verify-nysc-discharge.html